Index: firmware/App/Controllers/FlowSensors.c
===================================================================
diff -u -r5c53288436774f0cf6a24132ace29a64a66d619d -r0f4fbb2a56cdbe35dcedd9cad23867fd7248f86e
--- firmware/App/Controllers/FlowSensors.c	(.../FlowSensors.c)	(revision 5c53288436774f0cf6a24132ace29a64a66d619d)
+++ firmware/App/Controllers/FlowSensors.c	(.../FlowSensors.c)	(revision 0f4fbb2a56cdbe35dcedd9cad23867fd7248f86e)
@@ -18,8 +18,6 @@
 // ********** private definitions **********
 
 #define FLOW_SENSORS_DATA_PUB_INTERVAL               ( MS_PER_SECOND / TASK_PRIORITY_INTERVAL )  ///< Interval (ms/task time) at which the Dialysate flow data is published on the CAN bus.
-
-#define FLOW_SENSORS_ZERO_READING                       0xFFFF           // TODO remove                           ///< Flow sensor reading indicates zero flow (or flow lower than can be detected by sensor).
 #define FLOW_SENSORS_EDGES_BUFFER_LENGTH                100
 #define FLOW_SENSORS_PULSES_PER_LITER                   110000 // TODO calibration record
 
@@ -126,13 +124,15 @@
                 flowSensorStatus[ i ].measuredFlowLPM.data            = flowSensorStatus[ i ].measuredROFlowWithCPsLPM.data -
                                                                         ( getMeasuredPumpSpeed( CONCENTRATEPUMPS_CP1_ACID ) / ML_PER_LITER ) -
                                                                         ( getMeasuredPumpSpeed( CONCENTRATEPUMPS_CP2_BICARB ) / ML_PER_LITER );
+                flowSensorStatus[ i ].measuredFlowLPM.data            = MAX( flowSensorStatus[ i ].measuredFlowLPM.data, 0.0 );
                 break;
 
             case DIALYSATE_FLOW_SENSOR:
                 flowSensorStatus[ i ].edgeCountsBuffer[ countsIndex ] = getFPGADialysateFlowSensorEdgeCount();
                 oldest2CurrentEdgeDiff                                = u16DiffWithWrap( oldestEdgeCount, flowSensorStatus[ i ].edgeCountsBuffer[ countsIndex ] );
                 flowBeforeCalibrationLPM                              = oldest2CurrentEdgeDiff * FLOW_SENSORS_LITERS_PER_PULSES * SEC_PER_MIN;
                 flowSensorStatus[ i ].measuredFlowLPM.data            = getCalibrationAppliedFlowLPM( i, flowBeforeCalibrationLPM );
+                flowSensorStatus[ i ].measuredFlowLPM.data            = MAX( flowSensorStatus[ i ].measuredFlowLPM.data, 0.0 );
                 break;
 
 #ifndef _VECTORCAST_